How do you say “ancillary revenue streams” in Mandarin?

Nickelodeon execs hope to learn after launching “Ni Hao, Kai-lan,” the network’s bid to replicate the billion-dollar, bilingual success of “Dora the Explorer.”

The series, aimed at the increasingly coveted preschool demo, bows Feb. 7 at the start of the 15-day celebration of Chinese New Year. The debut of its 20-episode initial order caps an eventful four-year path to the screen that saw several launch delays, international production headaches, and the challenge of balancing education with entertainment value.

“We always worry about the curriculum seeming too didactic,” says Brown Johnson, a longtime Nick exec who now runs its preschool unit. “But Kai-lan has such a natural voice that the show feels organic as opposed to preachy.”

That blend did not come easily. The show not only sprinkles Mandarin phrases throughout its scripts (ni hao means “hello,” for example), but it pivots on a “social-emotional curriculum” that teaches toddlers how to deal with anger, jealousy, sadness and a host of other emotions.

An array of consultants was mobilized, and debates broke out regularly among them, the execs and the creatives about the proper approach to language, culture and emotion.

Adding to the complications was a partnership with Wang Films, which did physical animation work from Shanghai and Taiwan. The distance between Asia, the Burbank animation studio and execs in Gotham created a few anxious moments. Just before the show’s planned fall launch, which was touted at last summer’s TCA, the net realized the production bottleneck had resulted in too few episodes being ready.

For Nickelodeon, the stakes are higher than in the days it set the pace for preschool with “Dora” and “Blue’s Clues,” two innovative series that each contributed hundreds of millions in revenue from the late-1990s to the early 2000s.

“Dora,” which launched in 2000, remains on the air and brings in well over a billion dollars annually thanks to hundreds of consumer products, a live stage show and other ancillaries.

At the same time “Dora” and spinoff show “Go, Diego! Go” kept scoring, however, the preschool arena grew sharply more competitive. It exploded from a lean, “Barney” and “Sesame Street” landscape a generation ago to a battlefield of 50-plus shows a day on myriad cable and satellite channels.

This market has mushroomed in the absence of conclusive scientific evidence about what effect TV viewing has on young viewers. That hasn’t stopped the likes of Baby TV and BabyFirst TV from targeting viewers aged 3 to 36 months, or Irish production company JAM Media from opening its own actual preschool.

Originally titled “Downward Doghouse” when it was aiming to promote yogic concepts (a long story), “Ni Hao Kai-lan” centers on a 5-year-old Chinese-American girl who is the alter ego of creator Karen Chau. The twentysomething U.C. Irvine grad, hoping to become a children’s-book illustrator, created a website featuring her drawings of Kai-lan amid a vividly colored and whimsical animal menagerie.

When an underling sent producer Mary Harrington the drawings, which recalled the aesthetic of Japanese animator Hiyao Miyazaki (“Spirited Away”), she saw the makings of a series. As both a Nick exec and independent producer, Harrington had worked on hits like “Ren & Stimpy” and “Rugrats,” but preschool had never been on her resume.

The complicated, moving parts of “Ni Hao” caused her to good-naturedly remark several times during the show’s development that it was “the hardest show I’ve ever produced.”

Shorts for the Web were ordered, and that led to a full series order. No pilot was produced, unlike the usual procedure. That skipped step would haunt development of the show, because writers had to create backstories and educational precepts around characters who had abundant appeal but little original depth.

Married to songs by Matt Mahaffey, who runs pop-rap combo Self and has toured with Beck, the show has developed into an odd but absorbing amalgam. It’s not the first program to show toddlers Chinese language and culture (the Amy Tan-based “Sagwa” on PBS claims that honor), but its multihued palette and sing-song cheer will strike even preschool TV-savvy parents as unique.

Its creators believe the series has a good chance of connecting in the year of the Beijing Olympics. It should also play to achievement-obsessed U.S. families, whose pint-sized corporate warriors-to-be are learning Mandarin as the language of tomorrow’s business world. The services of Mandarin-speaking nannies and tutors have become scarce in major cities over the past few years.

There is another small but potent constituency: parents of the some 60,000 girls adopted in the U.S. from Chinese agencies. Nick, ever savvy in finding marketing hooks, has been promoting the fact that Jade-Lianna Gao Jian Peters, the voice of Kai-lan, is one of those children. Adopted at 8 months from Gao’an City in the Jiang Xi Province, she has grown up in Milwaukee.

Those combinations and contrasts are where the opportunities lie, Johnson believes. And she would know. She was the one who returned from a diversity conference and proposed that Dora the Explorer, then a redheaded Irish girl named Nina, speak Spanish.

“We really hope ni hao will be like vaminos on ‘Dora,'” Johnson says. “The sound of Chinese, with its up and down emphases and pronunciations, is so different to the Western ear. It’s great that we can expose kids to it at an early age.”